Apparatus comprising a plurality of interferometers and method of configuring such apparatus

Abstract

Embodiments of the invention relate to an apparatus and methods of using the apparatus wherein the apparatus includes a plurality of interferometers wherein the plurality of interferometers enable interference of an electromagnetic input signal, wherein the plurality of interferometers are configured to receive a plurality of sensor input signals from a plurality of sensors where the plurality of sensor input signals provide an indication of a plurality of sensed characteristics and the sensor input signals control the interference of the electromagnetic input signal by the plurality of interferometers, and wherein the plurality of interferometers are configured to provide a first output when the plurality of characteristics sensed by the sensors correspond to a first context and a second output when the plurality of characteristics sensed by the sensors correspond to a second context.

I claim: 
     
       1. An apparatus comprising:
 a plurality of interferometers wherein the plurality of interferometers enable interference of an electromagnetic input signal, and the plurality of interferometers is provided on a single chip; and 
 a plurality of sensors configured to provide a plurality of sensor output signals to the plurality of interferometers to control the interference of the electromagnetic input signal by the plurality of interferometers, wherein different sensors within the plurality of sensors are configured to sense different types of characteristics such that the plurality of sensor output signals provide an indication of a plurality of different types of sensed characteristics, 
 wherein the plurality of interferometers are configured to receive the electromagnetic input signal and receive the plurality of sensor output signals from the plurality of sensors to enable the sensor output signals to control the interference of the electromagnetic input signal by the plurality of interferometers, and 
 wherein the plurality of interferometers are configured to provide a first output signal when the plurality of different types of characteristics sensed by the sensors correspond to a first context and a second output signal when the plurality of different types of characteristics sensed by the sensors correspond to a second context. 
 
     
     
       2. An apparatus as claimed in  claim 1  wherein the apparatus comprises a plurality of phase shift elements configured to provide a phase shift in the electromagnetic input signal and to vary the phase shift in response to the sensor output signals to control the interference of the electromagnetic input signal by the plurality of interferometers. 
     
     
       3. An apparatus as claimed in  claim 1  wherein the sensor output signals control the interference of the electromagnetic input signal by the plurality of interferometers by controlling the coupling between two or more of the plurality of interferometers. 
     
     
       4. An apparatus as claimed in  claim 1  wherein each of the plurality of sensors is configured to sense a different characteristic. 
     
     
       5. An apparatus as claimed in  claim 1  wherein the electromagnetic input signal comprises a plurality of coherent components. 
     
     
       6. An apparatus as claimed in  claim 5  wherein the output signal comprises a plurality of components and in the first output signal a first component has the largest power level and in the second output signal a second, different component has the largest power level. 
     
     
       7. An apparatus as claimed in  claim 5  wherein the components of the electromagnetic input signal are selected so that the first output is provided when the plurality of different types of characteristics sensed by the sensors correspond to a first context and the second output is provided when the plurality of different types of characteristics sensed by the sensors correspond to a second context. 
     
     
       8. An apparatus as claimed in  claim 1  wherein the electromagnetic input signal comprises radiation with a wavelength between 100 nm and 2500 nm. 
     
     
       9. An apparatus as claimed in  claim 1  wherein the electromagnetic input signal is provided by a laser. 
     
     
       10. An apparatus as claimed in  claim 1  wherein the apparatus is also configured to receive one or more control inputs where the control inputs control the interference of the electromagnetic input signal by at least some of the plurality of interferometers. 
     
     
       11. An apparatus as claimed in  claim 10  wherein the control inputs are configured so that the first output is provided when the plurality of different types of characteristics sensed by the sensors correspond to a first context and the second output is provided when the plurality of different types of characteristics sensed by the sensors correspond to a second context. 
     
     
       12. An apparatus as claimed in  claim 1  wherein the plurality of interferometers may be modelled as an N×N matrix, where N is the number of components in the electromagnetic input signal and where the values of the elements in the matrix are given by the interference of the electromagnetic input signal caused by the plurality of interferometers. 
     
     
       13. An apparatus as claimed in  claim 12  wherein the values of the components of the electromagnetic input signal are selected to correspond to a combination of two different rows of the matrix. 
     
     
       14. A method comprising:
 configuring a plurality of interferometers to receive electromagnetic input signals and receive a plurality of sensor output signals from a plurality of sensors to enable the plurality of sensor output signals to be provided to the plurality of interferometers to control interference of the electromagnetic input signals by the plurality of interferometers, wherein different sensors within the plurality of sensors are configured to sense different types of characteristics such that the plurality of sensor output signals provide an indication of a plurality of different types of sensed characteristics, wherein the plurality of interferometers is provided on a single chip, and 
 configuring the plurality of interferometers to provide a first output signal when the plurality of different types of characteristics sensed by the plurality of sensors correspond to a first context and a second output signal when the plurality of different types of characteristics sensed by the plurality of sensors correspond to a second context. 
 
     
     
       15. A method as claimed in  claim 14  wherein configuring the interferometers to provide the first output signal and the second output signal comprises an iterative calibration procedure. 
     
     
       16. A method as claimed in  claim 15  wherein the iterative calibration procedure comprises selecting a first output signal to correspond to a first context and selecting a second output signal to correspond to a second context and providing known inputs by the plurality of sensors and varying the components of the electromagnetic input signal to find an electromagnetic input signal which provides the selected outputs for the respective contexts. 
     
     
       17. A computer program product comprising a non-transitory computer-readable storage medium bearing computer program instructions for causing a computer to perform the method of  claim 14 . 
     
     
       18. A method as claimed in  claim 14  wherein the plurality of interferometers comprise a plurality of phase shift elements configured to provide phase shifts in the electromagnetic input signal received by the interferometers, and the method comprises configuring the phase shift elements to receive the plurality of sensor output signals from the plurality of sensors to enable the plurality of phase shift elements to vary phase shifts in response to the sensor output signals to control the interference of the electromagnetic input signals by the plurality of interferometers. 
     
     
       19. A method as claimed in  claim 14  wherein the sensor output signals control the interference of the electromagnetic input signal by the plurality of interferometers by controlling the coupling between two or more of the plurality of interferometers. 
     
     
       20. A computer program product comprising a non-transitory computer-readable storage medium bearing computer program instructions that, when executed by at least one processor, enable:
 configuring a plurality of interferometers that are arranged to receive electromagnetic input signals and to receive a plurality of sensor output signals from a plurality of sensors to enable the plurality of sensor output signals to be provided to the plurality of interferometers to control interference of the electromagnetic input signals by the plurality of interferometers, wherein different sensors within the plurality of sensors are configured to sense different types of characteristics such that the plurality of sensor output signals provide an indication of a plurality of different types of sensed characteristics, wherein the plurality of interferometers is provided on a single chip; and 
 configuring the plurality of interferometers to provide a first output signal when the plurality of different types of characteristics sensed by the plurality of sensors correspond to a first context and a second output signal when the plurality of different types of characteristics sensed by the plurality of sensors correspond to a second context.